Snubbed bolster truck



Oct. 23, 1951 A. LEHRMAN SNUBBED BOLSTER TRUCK Filed March 5, 1948INVENTOR. Zea Q. Je/jmcz/z WWW Patented Oct. 23, 1951 S UB ED BOLSTERRUCK Leo A. Lehrman, Chicago, 111., assignor to American SteelFoundries, Chicago, 111., a corporation of New Jersey Application March5, 1948, Serial No. 13,171-

Claims, 1

This invention relates to railway car trucks and more particularly to animprovement on the structure shown in United States Letters Patent .No.2,378,414, Car Truck, issued on June 19, 1945, to David M. Light,

Expressed generally, the principal object of this invention is toprovide in a railway car truck, friction means between the side frameand the bolster for damping the vertical movements of the bolster, saidfriction means comprising a friction shoe pocketed in a column of theside frame in slidable engagement with column wedge surfaces slopingtoward said bolster, and a diagonally arranged spring reacting betweensaid shoe and the compression member of the side frame uniformlydistributed over the full friction face thereof, thus maintaining fullface engagement between the shoe and the bolster.

Another object of the invention is to arrange the parts of the frictiondevice in such a manner as to more effectively utilize the forcesexerted by the shoe-actuating spring.

A still further object of the invention is to provide a frictionassembly wherein the column wedge surfaces, the friction shoe wedgesurfaces and the spring'are cooperatively arranged to position thefriction shoe in such manner that it normally tends to have the frictionface thereof in full face engagement with the associated bolsterfriction surface and maintain said engagement during all movements ofthe bolster.v

These and other objects of the invention will be apparent from thespecification and the drawlugs, wherein: I

Figure 1 is a fragmentary sectional view of a railway car truckembodying my invention, the section being taken in a longitudinalvertical plane substantially as indicated by line l-| of Figure 2, onlyone end of the truck being shown inasmuch as it is similar at oppositeends thereof;

Figure 2 is a sectional view taken in the transverse horizontal planesubstantially is indicated by :the line 2--2 of Figure 1;

Figure 3 is a further sectional view taken in the vertical planesubstantially as represented by line 3 8 of Figure 1, the bolster,however, :bei

shown in phantom lines to more clearly illustrate the arrangement of thefriction shoe and the coland outboard spring-positioning flanges l4 and16. The widened top chord l2 affords a seat as at I8 for a set ofcompression springs 20, 20, said springs providing a'support for abolster 24.

The bolster is of box section and comprises a bottom wall 26 seated asat 212 on said springs, said bottom wall being provided with the usualspring-retaining lugs 28, 28 confining the beforementioned springstherebetween. The bolster also has a top wall 33, a sidewall 32 at eachside thereof, and a center rib 34. On the side walls of the bolster areprovided the usual inboard and outboard interlocking lugs 36 and 33which embrace the' column 6 therebetween. It will be noted that theoutboard guide lug is proportioned to fit through the widened portion llof the bolster opening to accommodate assembly and disassembly of thebolster with respect to the side frame in the conventional manner.

On each side Wall of the bolster between the inboard and outboardinterlocking lugs thereon is mounted a substantially vertical frictionplate 40 with upper and lower flanges 42, 42 recessed within the top andbottom of the bolster and embracing the bolster therebetween, thusinterlocking the friction plate with the bolster. The friction platemay, of course, be welded or otherwise secured to the bolster to be partthereof. The friction plate 40 cooperates with a friction shoe 44pocketed within the column 6 as hereinafter more particularly described.

The friction shoe is of skeletal construction somewhat cup-shaped inform and comprises vertically diverging front and rear walls .46 and .48and a bottom wall '50 angularly related to the horizontal plane of thebolster, that is, the plane of the bottom wall is at an oblique angle tothe vertical plane of the friction plate 40 of the bolster as best seenin Figure l. The front wall 46 of the friction shoe engages the frictionplate 40 as at 5! on a substantially vertical plane.

The shoe also comprises side walls 52, 52, generally triangular inshape, said side walls interconnecting said front and rear walls 46 and48. Each side wall 52 presents a diagonal or downwardly sloping crownedwedge surface 54 curved longitudinally thereof, these surfaces lying ina plane .disposed at an acute angle with respect to and sloping towardthe vertical friction surface on the friction plate of the bolster. Itwill be noted that the rear wall 48 of the shoe is arouately formedintermediate its ends and is cored away to form the curved surface 49 toafford clearance for a compression spring 56 which extends into the shoeand seats at its lower end on a spring seat or abutment surface 58 onthe bottom wall 50 of the shoe eccentrically of the central longitudinalmedian line of the shoe, that is, the spring is positioned adjacent therear wall of the shoe. aXisis at an acute angle to the vertical plane of"the friction plate 40 of the bolster and normal to the spring seatsurface 58 of the shoe. The lower end of the spring is positioned onsaid abutment surface 58 between surface 49 on the rear wall of the shoeand a reinforcing boss 59 formed with said bottom and front walls of theshoe at the juncture thereof. The upper end of the spring seats againstan abutment or spring seat surface 60 on the compression member 2,

said abutment surface being disposed in a plane substantially normal tothe axis of said spring 56,. or, in other words, substantially parallelto the spring seat surface 58 on the shoe. The abutment surface 68, inthe present instance, is the 'undersurface of a tie web or wall 62 whichconnects the lower ends of the inboard and outboard webs 64 and 65 ofthe compression member, said inboard and outboard webs merging with atop web 68 of the compression member, the compression member beinggenerally of inverted channel shape. One side of the upper end of thespring is positioned on the abutment surface 68 by means of a dependingboss or lug formed on said web 62 adjacent the bolster opening Ill andon its opposite side the spring is positioned by spaced transverselyextending slightly inclined webs I2, 12 formed on the inner edges of thespaced inboard and outboard walls 14 and 16 of column 6, these edgesbeing remote from the bolster opening.

The upper ends of walls 14 and I6 and webs 12, I2 merge with web 62 ofthe compression member, forming a pocket for the shoe at the upper endof the column, and the lower ends of webs .14 and i6 merge with thetension member. However, the lower ends of the webs 12, 12 terminate ashort distance below the upper ends of walls 14 and 16 and merge withthe inner ends of the bolster and lying in a plane substantiallyparallel to that of surfaces 54 on the lower ends of the side webs 52 ofthe shoe. The surfaces 54 and 88 engage each other tangentially (Figure1), the engagement occurring between related surfaces 54 and 80 at apoint 82, at the crest of surface 54, the points 82 being aligned withthe axis of the spring transversely of the side frame.

-By locating the point of engagement between the shoe and the ledges inthe plane of the axis of the spring, the shoe is normally held in theposition The spring is disposed so that its shown in Figure 1 with thefriction surface of the shoe in flat face engagement with plate 40. Thisarrangement avoids any tendency on the part of the spring to cant theshoe, thus providing for a substantially uniform distribution of theforces exerted by the spring over the full friction face of the shoe sothat even wear on the full face of the shoe and friction plate iseffected. The shoe does not tend to have edge contact with the bolsterfriction plate. Due to the manner of engagement between surfaces 54 and80, the shoe is capable of rocking within the column in accordance withthe canting or angling movements of the bolster and/or side frame. Inthis connection it will be noted that the points of engagement 82, 8.2between these surfaces are disposed much closer to the rear wall of theshoe than to the front or friction wall thereof. Inasmuch as the springis positioned adjacent the rear wall of the shoe, it in effect seats atone. side on the relatively short lever arm of the shoe, con sideringthe points 82 as points of pivot. This feature, in addition to the factthat the axis of the spring is aligned with the point of pivot orfulcrum (points 82, 82) of the shoe, reduces to the minimum bendingstresses on the spring during such rocking movement of the shoe,wherefore the life of the spring is considerably prolonged. In otherwords, the spring is seated on portions of the shoe which move much lessthan the friction surface of the shoe.

The lower end of column 6 is provided'with a web 84 connecting theinboard and outboard webs E4 and 16 of the column 6 at the forward edgesthereof defining the widened portion ll of the bolster opening. The web84 is cored away to form a substantially vertical slot 86 intermediatewebs I4 and 16 to accommodate downward movement of the friction shoe,the slot dividing the upper end of web 86 into spaced legs '81, B'Imerging with the forward ends of the ledges I8, 18'.

The rear wall 48 of the shoe is offset to form a loop 88'which projectsinto an opening or slot 98 (Figure 3) defined between the webs I2, 12

. of column 6. The loop 88 is designed to accommodate the insertion of apin therethrough for abutment with the adjacent edges of webs l4 and 16to lock the shoe in a retracted position in the column to facilitateassembly and disassembly of the bolster with respect to the side frame.

It will thus be apparent that the spring 56 is oriented to exert a forceagainst the shoe 44 in a plane diagonal to the plane of the frictionplate 48 on the bolster and that the spring 56 exerts a forcesubstantially normal to the bottom wall 50 of the shoe and web 62 of thecompression member, the surface 68 of the compressionmember and surface58 on the shoe lying in substantially parallel planes disposed at anobtuse angle to the vertical plane of the friction plate 48. The spring56 exerts a force on the shoe below the areas of engagement betweensurfaces 54 on the sides of the shoe and surfaces 80 on the ledges 18.It may also be noted that the transverse webs 12, 12 of the column areinclined from the vertical and substantially parallel to the plane ofthe adjacent portionsof the read wall 48 of the shoe, thus affording aclearance for the rear wall of the shoe to accommodate movement. of theshoe into the column upon lateral movement of the bolster 24 toward theshoe. Therear wall of the shoe other along generous bearing areas at. alocking asides;

angle friction to limit lateral movement of the bolster;

It is to be understood that :I do not wish to be limited by theexactembodiment of the device shown which is merely by way ofillustration and not limitation as various and other forms of thedevice'will, of course, be apparent to those skilled in the art withoutdeparting from the spirit f the invention or the scope of the claims.

I claim: i

1. A side frame comprising tension and compression members, a columnadjacent each end of said frame and comprisingspaced inboard andoutboard webs mergingat their lower and upper ends with said tensionandcompression 1 members respectively, and a wall interconnecting said websat one of their corresponding lateral edges at the lower ends thereofand merging with said tension member, said wall being bifurcatedintermediate the ends of said column to form spaced legs defining anupwardly opening slot, diagonally disposed coplanar ledges on theadjacent sides of said webs formed integral therewith and connected attheir lower ends to the upper ends of said legs, and spaced transversewebs on the other corresponding edges of said inboard and outboard websand merging at their upper ends with said compression member and attheir lower ends with the upper ends of said ledges.

2. In a railway car truck, a supporting member having a compressionmember and a column, a member spring-supported on said supporting memberand having a vertical friction surface adjacent said column, a pocket insaid column, a friction assembly in said pocket comprising a frictionshoe having a front wall in substantially vertical face frictionalengagement with said surface, wedge faces on said column at oppositesides of said shoe, wedge means at opposite sides of said shoe in wedgeengagement with said wedge faces, a spring extending between said facesand positioned eccentrically of the shoe and bearing thereagainst andagainst said compression member, means for positioning said spring onsaid compression member comprising a lug formed thereon and engageablewith one side of said spring, and spaced webs on said column at theopposite side of said spring.

3. In a railway car truck, a side frame having a pocket, a bolsterspring-supported from said frame, wedge means on said frame in saidpocket sloping toward said bolster, a friction shoe in said pocket andhaving vertically diverging front and rear walls, the formerfrictionally engaging said bolster, a bottom wall and spaced side wallsinterconnecting said front and rear walls, curved wedge surfaces on saidside walls engaging said wedge means, and a spring extending into saidshoe and seated at one end on said bottom wall and at its other endagainst said frame, the points of engagement of said surfaces with saidwedge means and the axis of said spring lying in a plane extendingtransversely of the frame.

4. In a railway car truck, a column member, a relatively movable membersupported adjacent thereto, friction means housed in one of saidmembers, said means comprising a shoe, vertically spaced substantiallyparallel inclined walls on said shoe and said one member respectively,cooperating wedge surfaces on said shoe and said last-mentioned memberintermediate said walls sloping toward the other member, and resilientmeans under compression between said walls, the points of engagement ofsaid surfaces and the "surface on one of said members, spaced wedgefaces on the other of said-members sloping to ward said surface anddisposed at an acute angle with respect thereto, a frictionelement-between said spaced wedge faces and having portions in wedgeengagement therewith, an abutment surface on said element spacedvertically with respectto said faces and lying in a-plane disposed at anobtuse angle with respect to said'ffiction surface, an abutment surfaceon said other memberspaced verticallyfrom said first-named abutmentsurface and lying in a plane substantially parallel thereto, andresilient means extending between and reacting against said abutmentsurfaces.

6. In a truck, a side frame member, a bolster member spring-supportedtherefrom, facing converging surfaces on said members arranged at anacute included angle therebetween, a shoe wedged between said surfaces,spring means reacting between said shoe and one of said members forurging the shoe into the'wedged position thereof, and complementaryengageable faces on said shoe and one of said members and arranged withrespect to the surface on the other member at an acute included angle oflesser magnitude than said included angle between said first-mentionedsurfaces, those of said faces on the lastmentioned one of said membersfacing the surface on said other member and being engageable with thoseof said faces on the shoe upon movement of the shoe in a direction awayfrom the surface on said other member to increase the resistance to saidmovement.

7. In a railway car truck, a side frame having a pocket, a bolstersupported from said frame adjacent said pocket, and friction means insaid pocket comprising a friction shoe having a front wall in frictionalengagement with said bolster along a substantially vertical plane, flatwedge surfaces in said pocket sloping toward said bolster, a springextending between said surfaces bearing against said shoe and said frameand spaced laterally of said front wall, and crowned wedge faces on saidshoe arranged to engage said surfaces at points aligned with the axis ofsaid spring transversely of said frame, said spring being oriented todeliver a force diagonally toward said bolster.

8. In a car truck, a side frame, a bolster supported therefrom, afriction shoe in said frame and having front and rear portions, saidfront portion frictionally engaging said bolster, cooperating wedgesurfaces on said shoe and frame sloping toward the bolster, and a springcompressed between said frame and said shoe, said spring extending intosaid shoe adjacent said rear portion thereof, said surfaces engagingeach other at points disposed in alignment with the axis of said springtransversely of said frame, said points being disposed closer to saidrear portion than to said front portion of said shoe.

9. A railway car truck comprising a frame, a bolster spring-supportedtherefrom, spaced coplanar wedge surfaces on the frame sloping towardthe bolster, a shoe extending between said surfaces and in wedgeengagement therewith and in frictional engagement with the bolster, anda spring sloping downwardly toward the bolster,

the upper end of said spring bearing against the frame and the lower endof said spring bearing against said shoe, the engagement between saidshoe and surfaces occurring in a plane containing the axis of saidspring and extending transversely of said frame.

10.'In a railway car truck, a side frame, a bolster spring-supportedtherefrom, a shoe pocketed in said frame and in frictional engage,- mentwith said bolster, a spring in said frame oriented to deliver a forcediagonally toward said bolster and reacting between said shoe and saidframe, and cooperating wedge surfaces on said frame and shoe engaged atpoints disposed with the axis of said spring in a plane extendingtransversely of the frame. 7 3

LEO A. LEHRMAN.

REFERENCES cI'rEii The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,894,385 Webb Jan. 17, 19332,159,138 Duryea May 23, 1939 2,852,693 Davidson Ju1y'4, 1944 2,366,957Cottrell Jan. 9,1945 2,378,414 Light June19, 1945 2,422,638 Tucker June17, 1947 2,425,822 Olander Aug. 19, 1947 2,427,194 Clasen Sept. 9,- 19472,434,583 Pierce Jan. 13, 1948 2,458,210 Schlegel Jan. 4, 1949 2,483,181Clasen Sept. 27, 1949

